0401 - E120 - Civil Codes and Inspection - 04 - Loads ...Load Types (ASCE 7‐05) • D = dead load...

Training Course onTraining Course onCivil/Structural Codes and Inspectionp

BMA Engineering, Inc.

1BMA Engineering, Inc. – 4000

Overall OutlineOverall Outline

1000. Introduction

4000. Federal Regulations, Guides, and Reports

3000. Site Investigation

4000. Loads, Load Factors, and Load Combinations

5000. Concrete Structures and Construction

6000. Steel Structures and Construction

7000. General Construction Methods

8000. Exams and Course Evaluation

9000. References and Sources



• Objective and Scope– Introduce loads, load factors, and load , ,combinations for nuclear‐related civil & structural design and constructiong

– Present and discuss• Types of loads and their computational principles• Types of loads and their computational principles

• Load factors

• Load combinations• Load combinations

• Focus on seismic loads

• Computer aided analysis and design (brief)• Computer aided analysis and design (brief)

BMA Engineering, Inc. – 4000 3

Scope: Primary Documents CoveredScope: Primary Documents Covered

• Minimum Design Loads for Buildings and Other Structures [ASCE Standard 7‐05]

• Seismic Analysis of Safety‐Related Nuclear Structures and Commentary [ASCEStructures and Commentary [ASCE Standard 4‐98]

• Design Loads on Structures During Construction [ASCE Standard 37‐02]Construction [ASCE Standard 37 02]


Load Types (ASCE 7‐05)• D = dead load

yp ( )

• Di = weight of ice

• E = earthquake loadq

• F = load due to fluids with well‐defined pressures and maximum heightsmaximum heights

• Fa = flood load

H l d d l l h d• H = load due to lateral earth pressure, ground water pressure, or pressure of bulk materials

• L = live load


Load Types (ASCE 7‐05)• Lr = roof live load

yp ( )

• R = rain load

• S = snow load

• T = self‐straining force

• W = wind load• W = wind load

• Wi = wind‐on‐ice loads


Dead Loads, Soil Loads, and H d t ti P

• Dead loads consist of the weight of all materials of

Hydrostatic PressureDead loads consist of the weight of all materials of construction incorporated into the building, e.g.,– Walls, floors, roofs, ceilings, stairways, built‐in partitions,Walls, floors, roofs, ceilings, stairways, built in partitions, finishes, cladding, and other fixed service equipment including weight of cranes

• Unit weight of materials and dimensions of componentsp

• Soil loads, lateral pressure, hydrostatic loads, and upliftuplift


Dead Loads


Live Loads• A load produced by the use and occupancy of the b ld h h d l dbuilding or other structure that does not include construction or environmental loads, such as wind l d l d l d h k l d fl dload, snow load, rain load, earthquake load, flood load, or dead load

• Tabulated unit loads by occupancy and use of a structure


Dead or Live Loads

• Tributary area and live load reductionTributary area and live load reduction


Flood Loads• They apply to structures located in areas prone to flooding and includeflooding, and include– Hydrostatic loads

H d d i l d ( i )– Hydrodynamic loads (moving)

– Wave loads (repeated impact)

• Structures shall be designed, constructed, connected, and anchored to resist flotation, collapse, and permanent lateral displacement due to action of flood loads associated with the design flood and other loads in accordance with load combinations

• The effects of erosion and scour shall be included in the calculation of loads


Wind Loads• Structures shall be designed and constructed to resist wind loads computed based in specified windresist wind loads computed based in specified wind speed and various wind & pressure coefficients:

Si lifi d d f l d b ildi– Simplified procedure for commonly used building geometries, closures, and stiffness without torsion

Analytical procedure for regular shaped without special– Analytical procedure for regular‐shaped without special wind‐related effects including torsion

– Wind tunnel procedure is permitted in lieu of the above– Wind tunnel procedure is permitted in lieu of the above two methods for any building or structure


Wind Loads: Wind Speed


Wind Loads: Wind SpeedpImportance Factors: Degree of hazard to human life andof hazard to human life and damage to property


Method 1: Simplified Procedurep


Method 2: Analytical Procedurey






Method 2: Analytical ProcedureProcedure

Main wind force resisting system


Method 3: Wind Tunnel

Burj DubaiBurj Dubai


Wind Load Effects


Wind Load EffectsTacoma Narrow Bridge – See also video file: Tacoma Bridge


Snow LoadsSnow load for flat roof (f) (<5%)

IpCCp 70 gtef IpCCp 7.0

p ground snow loadpg = ground snow load (tabulated)Exposure and thermal factorsExposure and thermal factors


Ground Snow Loads


Snow Loads


Rain Loads• Rain load on the undeflected roof, i.e., rain loads computed without any deflection from loadscomputed without any deflection from loads (including dead loads)

d b d f d• Loads based on roof drainage systems

• Ponding instability, where “Ponding” refers to the retention of water due solely to the deflection of relatively flat roofs


Ice Loads• Atmospheric ice loads due to freezing rain, snow, and in cloud icing shall be considered in the design of icein‐cloud icing shall be considered in the design of ice‐sensitive structures

l f• 50‐year mean recurrence interval uniform ice thickness due to freezing rain (next slide)


Ice Loads


Seismic Analysis (ASCE 4‐98)y ( )Earthquakes, F lt Pl tFaults, Plate Tectonics, E th St tEarth Structure

See video: 10.5‐ Earthquake in San Francisco! See video 10.5‐M7.0 Earthquake Simulation for Hayward Fault, California


See video 10.5‐ Earthquake Destructionfor Hayward Fault, California

Seismic Analysis (ASCE 4‐98)y ( )• The Niigata-ken Chuetsu-oki TOKYO ELECTRIC POWER COMPANY

Earthquake (NCOE) occurred in 2007

• The Kashiwazaki Kariwa Nuclear P St ti l t d i thPower Station located in the same area

• The station was hit by a big tremor more than its intensity assumed tomore than its intensity assumed to be valid at the station design stage

• Preventive functions for the station safety worked as expected as itsafety worked as expected as it designed

• Critical facilities designed as high seismic class were not damagedseismic class were not damaged, though considerable damages were seen in outside-facilities designed as low seismic class


as low seismic class

Seismic Analysis (ASCE 4‐98)y ( )


Seismic Analysis (ASCE 4‐98)y ( )In case of a release, prevailing wind predicted fallout pattern


Seismic Analysis (ASCE 4‐98)y ( )Earthquake load

• Requirements for performing analyses on structures under earthquake motionstructures under earthquake motion

• Provide rules and analysis parameters that produce seismic responses with same p oduce se s c espo ses sa eprobability of non‐exeedance as the input

• Specifications of input motions

• Analysis standards for modeling of structures

• Soil structure interaction modeling and ganalysis

• Input for subsystem seismic analysis

B di l t

• Special structures

• Seismic probabilistic risk assessment and


Base displacementseismic margin assessments

20

25

10

15

20

5

10

-5

0

-15

-10

-25

-20

TIME - seconds

0 1 2 3 4 5 6 7 8 9 10

Typical Earthquake Ground Acceleration - Percent of Gravity


2

0

- 4

- 2

- 6

- 4

- 8

- 10

0 1 2 3 4 5 6 7 8 9 10TIME - seconds

- 12

Absolute Earthquake Ground Displacements - Inches35BMA Engineering, Inc. – 4000

20

16

18

12

14

8

10

1 0 Percent Damping

4

6

1.0 Percent Damping 5.0 Percent Damping

0

2

0 1 2 3 4 5

PERIOD - Seconds

Relative Displacement Spectrum y (T) InchesRelative Displacement Spectrum y (T)MAX Inches


90

100

70

80

90

1 0 P t D i

60

70 1.0 Percent Damping 5.0 Percent Damping

40

50

20

30

0 1 2 3 4 50

10

0 1 2 3 4 5

PERIOD - SecondsMAXa yS )(2

Pseudo-Acceleration Spectrum Percent of GravityMAXa y )(


Seismic Analysis (ASCE 4‐98)• Steps in design and construction process that l d h l b l f l f l d

y ( )

lead to the reliability of nuclear safety‐related structures under earthquake motion– Definition of seismic environment

– Analysis to obtain seismic response informationAnalysis to obtain seismic response information

– Design or evaluation of the structural elements

– Construction


Seismic Analysis (ASCE 4‐98)• Provides requirements for designing new f l d l f f l

y ( )

facilities and evaluation of existing facilities

• Intent of analysis methodologyy gy– Output parameters maintain same non‐exceedance probability as inputexceedance probability as input

– Example: produce seismic responses that have b t 90% h f t b i d d fabout a 90% chance of not being exceeded for an input response spectrum specified at the 84th

tilpercentile


Seismic Analysis (ASCE 4‐98)• Analysis provides small levels of conservatism

f

y ( )

to account for uncertainty– Soil‐structure interaction

– In‐structure response spectra

– Structural damping– Structural damping

• Analysis output has slightly greater probability of non‐exceedance than that for inputsp


NUREG 0800• Applicable to Structures, Systems and

( )Components (SSCs)

• Two earthquake intensitiesq– Safe‐shutdown earthquake ground motion (SSE)

S f ti th k d ti (SOE)– Safe‐operation earthquake ground motion (SOE)

• Category I SSCs are SSCs designed to remain functional if the SSE occurs


NUREG 0800 Section 3.0: Design of Structures, Components, Equipment, and Systems

• Seismic (3.7.1 to 3.7.4)

Three spatial componentsEarthquake Design

parameters

Seismicity & geologic conditions

1. Operating basis earthquake (OBE)

2. Safe shutdown earthquake (SSE)

Three spatial components of ground motion (two horizontal and one vertical)

Structures, systems & components

Ground motion response spectra

(GMRS)

Site‐specific GMRS

Design response spectra for seismic category I SSCs at top of first p

(SSCs)(GMRS)

Design time histories (if

Use 3‐compnent cancelation time history

1. Percentages of critical damping

psurface of soil materials

S i i l i fhistories (if design spectra unavailable)

yif available; otherwise generate using design

spectra

critical damping

2. Support/foundation media

Seismic analysis of category I SSCs



Power Spectral Density• Seismic (3.7.1 to 3.7.4)Power Spectral Density (PSD) in in2/sec3 for Western US (WUS)



• Seismic (3.7.1 to 3.7.4)

Same Level:1. Ground motion

response spectra (GMRS)

2. certified seismic design

If CSDRS > GMRS and site & design condition are

met, CSDRS are adequate; otherwise evaluate using an appro ed method*

Not Same Level:1. Ground motion response

spectra (GMRS)

2. certified seismic design

If CSDRS > FIRS and site & design condition are met, CSDRS are adequate;

otherwise evaluate using an approved method*g

response spectra (CSDRS)

Develop foundation level t i t t ith Ch k if i i

an approved method* response spectra (CSDRS)

Develop foundation level spectra and foundation input

pp

spectra consistent with CSDRS for each Category I

SSC

Check if minimum spectrum is met

spectra and foundation input response spectra (FIRS)

consistent with CSDRS for each Category I SSC

Check if minimum spectrum is met

* Approved method accounts for soil-structure interaction (SSI), torsion, rocking, in-structure response, redesign, re-analysis as needed until limits are met. Cases without a certified design require developing GMRS, smoothed response spectra, foundation-


level response spectra, analysis, redesign & reanalysis until meeting limits.


• Seismic (3.7.1 to 3.7.4)– Analysis methods:y

• Response spectrum method

• Time history analysis methodTime history analysis method

• Equivalent static load analysis method

– Natural frequencies and response– Natural frequencies and response

– Material, damping, stiffness and mass properties

– Hydrodynamic effects



• Seismic (3.7.1 to 3.7.4)– Soil‐structure interaction (SSI):( )

• The random nature of the soil and rock configuration and material characteristics

• Uncertainty in soil constitutive modeling (soil stiffness, damping, etc.)

• Nonlinear soil behavior

• Coupling between the structures and soil

• Lack of uniformity in the soil profile, which is usually assumed to be uniformly layered in all horizontal


directions


• Seismic (3.7.1 to 3.7.4)– Soil‐structure interaction (SSI) (cont.):( ) ( )

• Effects of the flexibility of soil/rock

• Effects of the flexibility of basematEffects of the flexibility of basemat

• The effect of pore water on structural responses, including the effects of variability of ground‐water level g y gwith time

• Effects of partial separation or loss of contact between the structure (embedded portion of the structure and foundation mat) and the soil during the earthquake


• Strain‐dependent soil properties


• Seismic (3.7.1 to 3.7.4)– Interaction of non‐category I structures with g yCategory I SSCs (decoupling criteria based on mass ratios and fundamental frequency ratios)q y )

– Effects of parameter variation on floor responses

Use of equivalent vertical static factors– Use of equivalent vertical static factors

– Methods used to account for torsional effects

– Procedures for damping

– Overturning moments and sliding forces


g g


• Seismic (3.7.1 to 3.7.4)– Seismic analysis to cover Category 1 subsystems y g y yusing similar approaches deployed for SSCs:

• PlatformsPlatforms

• Support frame structures

• Yard structuresYard structures

• Buried piping, tunnels and conduits

• Concrete damsConcrete dams

• Atmospheric tanks



• Seismic (3.7.1 to 3.7.4)– Seismic analysis to cover instrumentation (per RG y (p1.12 and RG 1.66)

ASCE 7 ASCE 4 ASCE ASCE 7 ASCE 4 37


Seismic Analysis (ASCE 4‐98)• Type of Structures

y ( )

– All safety related structures of nuclear facilities

• Assumes foundation material stabilityAssumes foundation material stability

• Determined seismic responses to be bi d ith d t d d l dcombined with responses due to dead loads

and other loads


Seismic Analysis (ASCE 4‐98)

• Seismic ground motions • Modeling of structures

Seismic Input Analysis• Seismic ground motions

R t

• Modeling of structures

A l i f t t• Response spectra • Analysis of structures

• Soil structure interaction• Time histories • Soil‐structure interaction modeling and analysis

• Power spectral density functions


• Additional requirements for structures sensitive to • Special structures


long period motions


• Seismic ground motions

Seismic Input• Seismic ground motions

R t• Response spectra

• Time histories

• Power spectral density functions

• Additional requirements for structures sensitive to long period


motions

Seismic Inputp

• Seismic Ground Motions– Two orthogonal horizontal and one vertical componentscomponents

– Appropriate for geological and seismological environment and subsurface conditionsenvironment and subsurface conditions

– Free field ground surface motion at top of t f d ti t i lcomponent foundation material

– Specified in terms of peak ground acceleration (PGA), peak ground velocity (PGV), and response spectra


Seismic Inputp• Seismic Ground Motions (cont.)

– peak ground displacement if required (PGD) and Effective duration of seismic motion to be included if required

• Nonlinear effects in foundation soils, special structures, structural response

– Appropriate for the magnitude and distance of the largest contributor design earthquakes to the seismic hazard for the site


Seismic Inputp• Respond Spectra

– General requirements

– Site‐specific horizontal response spectraSite specific horizontal response spectra

– Site‐independent horizontal response spectra

V ti l t– Vertical response spectra


Seismic Inputp• Respond Spectra ‐ General Requirements

– Either site specific or standard

– Response spectrum for an intermediate damping p p p gfactor

– Consider two potential ground motions separatelyConsider two potential ground motions separately


Seismic InputSeismic Input• Respond Spectra ‐ Site‐Specific Horizontal Response Spectra

– Necessary for sites with soft soils, i.e., soils having y , , ga low strain shear wave velocity of no greater than 750 ft/s averages for the top 100 ft of soil/ g p

– Sites of hgh frequency motions > 33 Hz

Facilities within 15 km of active fault– Facilities within 15 km of active fault


Seismic InputR d S Si S ifi H i l R• Respond Spectra ‐ Site‐Specific Horizontal Response Spectra: a comparison (high‐frequency content)

1 2

1.0

1.2

AP 1000

0.8

n (g

) Bellefonte

0.6

Acc

eler

atio

n

0.2

0.4 Shearon Harris

0.01 10 100


1 10 100

Frequency (Hz)

Comparisons are between certified design spectra and 10‐4 site specific spectra

Seismic InputSeismic Input• Respond Spectra ‐ Site‐Independent Horizontal Response Spectra using:

– Spectral acceleration (Sa)p ( a)

– Spectral velocity (Sv)

Spectral displacement (S )– Spectral displacement (Sd)

• Computed using the dynamic amplification factors

• Instead of median,other exceedanceprobability can be used


Seismic InputSeismic Input• Respond Spectra ‐ Site‐IndependentIndependent Horizontal Response SpectraSpectra

• Example: d h dMedian‐shaped

response spectrum for h lhorizontal motion scaled to 0.3g peak

d l iground acceleration, 5% damping, soil site


Seismic Inputp• Respond Spectra ‐ Vertical Response Spectra

– Use a value of 2/3 of the corresponding horizontal component throughout the frequency rangep g q y g

– For source to site distance < 15 km, use the following factorsfollowing factors

• 1 for frequency > 5 Hz

• 2/3 at frequency < 3 Hz• 2/3 at frequency < 3 Hz

• Linear interpolation for cases in between 3 and 5, unless a site‐specific evaluation is conductedunless a site specific evaluation is conducted


Seismic Inputp• Time Histories

– Use duration envelope function foreach direction


Seismic Inputp• Time Histories

– Compute spectral valuesat sufficient points

– Use orthogonal components p


Seismic Inputp


Seismic Inputp• Power Spectral Density (PSD) Functions

– PSD is computed from time histories using Fourier transformation

– For zero‐mean stochastic processes, spectral density is the variance as a function of frequencydensity is the variance as a function of frequency

– It is related to energy as a function of frequency


Seismic Inputp

• Additional Requirements for Structures Sensitive to Long Period Motionsg– Structures for which isolation techniques, liquefaction and hydrodynamic effects areliquefaction and hydrodynamic effects are considered

Response spectral for 0 2 to 33 Hz with smaller– Response spectral for 0.2 to 33 Hz, with smaller frequencies requiring site‐specific analysis

Ti hi t i b d f i l– Time histories can be used for special cases



• Modeling of structures

Analysis• Modeling of structures

A l i f t t• Analysis of structures

• Soil structure interaction modeling• Soil‐structure interaction modeling and analysis


• Special structures


Seismic Analysisy• Modeling of Structures

– General requirements

– Structural material propertiesStructural material properties

– Modeling of stiffness

M d li f– Modeling of mass

– Modeling of damping

– Modeling of hydrodynamic effects

– Dynamic coupling criteriaDynamic coupling criteria

– Requirements for modeling specific structures


Seismic Analysisy

• Modeling of Structures ‐ General RequirementsModeling of Structures General Requirements– Models for horizontal and vertical motions can be separate if the motions are uncoupled; otherwiseseparate if the motions are uncoupled; otherwise 3‐D analysis is required

O t th d f i i l i– One‐step method for seismic response analysis

– Multistep method for seismic response analysis• In the first step, and overall response is obtained and used as an input to the second step, and so on

– Discretization considerations (mesh size, finite element type, reduction of degrees of freedom, etc.)


Seismic Analysisy

• FiniteFinite element analysisanalysis


Seismic Analysisy

• FiniteFinite element analysisanalysis


BMA Engineering, Inc. – 4000 73 BMA Engineering, Inc. – 4000 74

BMA Engineering, Inc. – 4000 75 BMA Engineering, Inc. – 4000 76

Seismic Analysisy

• Modeling of Structures ‐ Structural Material gProperties– Modulus of elasticity for concrete (ACI code)– Modulus of elasticity for concrete (ACI code) , steel (29,000 ksi), aluminum (10,000 ksi)

P i ’ ti f t (0 17) t l (0 3)– Poisson’s ratio for concrete (0.17) , steel (0.3), aluminum (0.3)

– Damping


Seismic Analysisy

• Modeling of Structuresg– Stiffness

• Steel and aluminumSteel and aluminum

• Concrete (cracked or un‐cracked)

Mass– Mass• Discretization

M d l t i l d ll t ib t h fi d• Modal mass to include all tributary mass such as fixed equipment, piping, etc.

D i– Damping • Superposition of properties for a system of subsystems


Seismic AnalysisyModeling of h d d ihydrodynamic effects


Seismic AnalysisyDynamic coupling criteria


Seismic Analysisy

• Requirements for Modeling Specific Structuresq g p– Structures with rigid floors

• Degrees of freedomDegrees of freedom

• Model type, e.g., lumped sum mass

Structures with flexible floors– Structures with flexible floors

– Framed structures

– Shear‐wall structures

– Plate and shell structures

– Adjacent structures (spacing requirements)


Seismic Analysisy

• Analysis of Structuresy– Time history method

Response spectrum method– Response spectrum method

– Complex frequency response method

– Equivalent static load method

• Three orthogonal componentsg p– Two horizontal

O ti l– One vertical


Seismic Analysisy

• Time history method: linear methods

gh uUMXKXCXM }]{[}]{[}]{[}]{[ where M = mass, C = damping, K = stiffness, , p g, ,X = displacement, X dot = velocity, X two-dots = acceleration, U = influence vector, , ,u = ground acceleration

• Discretization min step sizeDiscretization, min step size • Solution methods

M d l iti– Modal superposition– Integration


Seismic Analysisy• Approximations

– The loads are applied directly to the structure– In the case of a real earthquake, q ,

displacements are applied at the foundation of the real structure


Seismic Analysisy• Time history method• Sources of nonlinearities

– Materials– Geometries


Seismic Analysisy• Response spectrum method

– Linear methods

– Nonlinear methodsNonlinear methods

• Complex frequency response methodR ti hi t– Response time history

– Transfer functions (ratios of Fourier transform of response to Fourier transform of input)

• Equivalent static load methodq– Cantilever model with uniform mass distribution


Soil‐Structure Interaction (SSI)( )• Soil-structure interaction modeling and analysis

– Required for structures not supported by rock or rock‐like soil foundation material

– Two methods

• Direct method• Direct method

• Impedance function approach

– Fixed‐base analysis


Soil‐Structure Interaction (SSI)( )• Fixed‐base analysis (nonlinearity, uncertainties)


Soil‐Structure Interaction (SSI)( )• Fixed‐base analysis (nonlinearity, uncertainties)


Soil‐Structure Interaction (SSI)( )• Subsurface material properties

– Shear modulus

– Horizontal damping ratioHorizontal damping ratio

– Poisson’s ratio


Shear Modulus


Damping Ratiop g


Damping StiffnessDamping Stiffness


Soil‐Structure Interaction (SSI)( )• Direct method, steps:

– Locate the bottom and lateral boundaries of the SSI model

– Establish input motion at the boundaries

• Soil element size• Soil element size

• Time step and frequency increment


Soil‐Structure Interaction (SSI)( )• Impedance method, steps:

– Determine the input motion to the mass‐less rigid foundation

– Determine the foundation impedance (defined as force‐i i d l i ) f iresistance to motion measured as velocity) function

– Analyze the coupled soil‐structure system

• Impedance function can be determined using– Equivalent dimensions for mat foundations

– Equivalent impedance for layered soil sites

– Approximations relating to embedded foundationspp g

• Analysis of coupled soil‐structural system


Soil‐Structure Interaction (SSI)• Input for sub‐system seismic analysis

( )

– Generation of seismic input for all systems and components which are not specifically modeled in p p ythe main dynamic model

• In‐structure response spectra• In‐structure response spectra– Time history method

– Frequency intervals

– Uncertainties and interpolation

• In‐structure time history


In Structure Responsep


Special Structuresp• Buried pipes and conduits

• Earth‐retaining walls

• Above ground vertical tanks• Above ground vertical tanks

• Raceways including cable trays and conduit systems

• Base isolated structures• Base isolated structures


Special Structuresp• Earth‐retaining walls


Damping of Conduitsp g


Special Structuresp• Earth‐retaining walls


Special Structuresp


Seismic Probabilistic Risk A t (SPRA)Assessment (SPRA)







SMA = Seismic Margin Earthquake (l th th d i b i )


(larger than the design basis)


HCLPF = High Confidence Low Probability of Failure


Probability of Failure


SMA = Seismic Margin Assessment


Load Factors and Load Combinations• Normal Loads: encountered during normal plant start‐up, operation, and shutdownp p, p ,

ANSI/AISC N690‐06


Load Factors and Load Combinations

• Severe Environmental Loads: encountered infrequently during the service life ANSI/AISC

N690‐06


Load Factors and Load Combinations• Extreme Environmental Loads: highly improbable b t are sed as a design basis

ANSI/AISC N690‐06

improbable but are used as a design basis


Load Factors and Load Combinations• Abnormal Loads: generated by a post lated high energ pipe break accident

ANSI/AISC N690‐06

postulated high‐energy pipe break accident used as a design basis


Load Factors and Load Combinations• Load and Resistance Factor Design (LRFD)

ANSI/AISC N690‐06

(LRFD) – The design strength (φRn) of each structural component shall be equal to or greater than the required strength (Ru), determined from the appropriate critical combinations of the loads

– The most critical structural effect may occur when yone or more loads are not acting


Load Factors and Load Combinations• LRFD Normal Load Combinations

ANSI/AISC N690‐06


Load Factors and Load Combinations• LRFD Severe Load Combinations

ANSI/AISC N690‐06

• LRFD Extreme and Abnormal Load Combinations


Load Factors and Load Combinations• Allowable Stress Design (ASD)

h ll bl h ( / ) f h l

ANSI/AISC N690‐06

– The allowable strength (Rn/Ω) of each structural component shall be equal to or greater than the

i d h ( ) d i d f hrequired strength (Ra), determined from the appropriate critical combinations of the loads

– The most critical structural effects may occur when one or more loads are not acting


Load Factors and Load Combinations• ASD Normal Load Combinations

ANSI/AISC N690‐06


Load Factors and Load Combinations• ASD Severe Load Combinations

ANSI/AISC N690‐06

• LRFD Extreme and Abnormal Load Combinations




• Seismic Analysis of Safety‐Related Nuclear Structures and Commentary [ASCE Standard 4‐98]

• Design Loads on Structures During Construction [ASCE Standard 37‐02] [ ]


Design Loads on Structures During Construction [ASCE Standard 37‐02]

• GeneralGeneral– Purpose: Minimum design load requirements d i t tiduring construction

– Scope: Partially completed structures and temporary structures

– Basic Requirements:• Safety

• Structural integrityg y

• Serviceability

• Load typesyp

• Construction methodsBMA Engineering, Inc. – 4000 120


• Loads and Load Combinations– Loads Specifiedp

• Dead and live loads

• Construction loads (temporary structures, etc.)Construction loads (temporary structures, etc.)

• Material loads

• Construction procedure loadsConstruction procedure loads

• Lateral earth pressure

• Environmental loads (thermal snow earthquake rainEnvironmental loads (thermal, snow, earthquake, rain, ice)



• Loads and Load Combinations– Load Combinations and Load Factors for Strength gDesign

Combined design load = dead load and/orCombined design load = dead load and/or material load + loads at their max value + loads at their APT reduced valuestheir APT reduced values

bi i i iAPT = arbitrary point in time



• Construction Loads– General Requirementq

– Material Loads

Personnel and Equipment Load– Personnel and Equipment Load

– Horizontal Construction Loads

– Erection and Fitting Forces

– Equipment Reactionsq p

– Form Pressure

Application of Loads– Application of Loads



• Basic Combinations (example)1.4 D + 1.4 CD + 1.2 CFML + 1.4 CVMLD FML VML

D = dead load

C construction dead loadCD = construction dead load

CFML = fixed material load

CVML = variable material load



• Loads and Load Combinations– Overturning and slidingg g

– Allowable Stress Design

Bridges (use AASHTO Code)– Bridges (use AASHTO Code)


Computer Aided Analysis and Designp y g

• Finite element analysis

• Software


Computer Aided Analysis and Designp y gSteps


Computer Aided Analysis and Designp y gElements and degrees of freedomExample

• 2D or 3D point‐to‐point or thru curve

• 6 translational DOFs at nodes

Beam Elements

• Shown in light blue with cross‐section (Shown here in red for clarity)

• Well suited to represent beams with a 10:1


Well suited to represent beams with a 10:1 slenderness ratio

Computer Aided Analysis and Designp y gElements and degrees of freedomExample

• Tetrahedral shape

• 3 translational DOFs at nodes

• Rotational constraints not required

Shell element

Rotational constraints not required

• Shown in blue

• Ideal for solid bodies with large cross‐sectional areas


• Not well suited for thin bodies

Computer Aided Analysis and Designp y gMaterials


Computer Aided Analysis and Designp y gConstraints



Symmetry constraintsSymmetry constraints



Loads



Mesh and controlMesh and control


Computer Aided Analysis and Design

Connections and SpringsBonded

Connections and Springs

FreeFree

S i

Contact – no Interpenetration

Springs



Analysis definitionAnalysis definition


Computer Aided Analysis and Designp y gResults


Computer Aided Analysis and DesignResults


Computer Aided Analysis and DesignOpen source software (source Wikipedia)

p y g

• CalculiX is an Open Source FEA project. The solver uses a partially compatible ABAQUS file format. The pre/post‐processor generates p /p p ginput data for many FEA and CFD applications

• Code Aster French software written in Python• Code Aster: French software written in Python and Fortran, GPL license

• DUNE, Distributed and Unified NumericsEnvironment GPL Version 2 with Run‐TimeEnvironment GPL Version 2 with Run Time Exception, written in C++

FEBi Fi i El f Bi h i• FEBio, Finite Elements for BiomechanicsBMA Engineering, Inc. – 4000 139


p y g

• Elmer FEM solver: Open source multiphysicalsimulation software developed by Finnish Ministry of Education's CSC, written in C, C++ y , ,and Fortran

• FEniCS Project a LGPL licensed software• FEniCS Project: a LGPL‐licensed software package developed by American and European researchers

• Hermes Project: Modular C/C++ library forHermes Project: Modular C/C++ library for rapid prototyping of space‐ and space‐time adaptive hp FEM solversadaptive hp‐FEM solvers



p y g

• Impact: Dynamic Finite Element Program Suite, for dynamic events like crashes, written in Java, GNU license,

• OOFEM: Object Oriented Finite EleMentsolver written in C++ GPL v2 licensesolver, written in C++, GPL v2 license

• OpenSees is an Open System for Earthquake Engineering Simulation

• Z88: FEM software available for Windows and• Z88: FEM‐software available for Windows and Linux/UNIX, written in C, GPL license


Computer Aided Analysis and DesignCommercial software (source Wikipedia)

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• Abaqus: Franco‐American software from SIMULIA, owned by Dassault Systemes

• ADINAADINA

• ALGOR Incorporated

• ANSA: An advanced CAE pre‐processing software for complete model build up.software for complete model build up.

• ANSYS: American software

• COMSOL Multiphysics COMSOL MultiphysicsFinite Element Analysis Software formerly y yFemlab



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• Femap, Siemens PLM Software: A pre and post processor for Windows

• FlexPDEFlexPDE

• Flux : American electromagnetic and thermal FEA

• JMAG: Japanese software Actran: BelgianJMAG: Japanese software Actran: Belgian Software (Acoustic)

LS DYNA LSTC Li S ft• LS‐DYNA, LSTC ‐ Livermore Software Technology Corporation

• LUSAS: UK SoftwareBMA Engineering, Inc. – 4000 143


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• MADYMO: TASS ‐ TNO Automotive Safety Solutions

• Nastran: American softwareNastran: American software

• nastran/EM: Nastran Suit for highly advanced Durabilty & NVH Analyses of Engines; born from the AK32 Benchmark of Audi, BMW, Daimler, Porsche & VW; Source Code available

• NEi Fusion NEi Software: 3D CAD modeler +• NEi Fusion, NEi Software: 3D CAD modeler + Nastran FEA



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• NEi Nastran, NEi Software: General purpose Finite Element Analysis

• NEi Works NEi Software: Embedded NastranNEi Works, NEi Software: Embedded Nastranfor SolidWorks users

• NISA: Indian software

• PZFlex: American software for wavePZFlex: American software for wave propagation and piezoelectric devices

Q i kfi ld Ph i i l ti ft• Quickfield : Physics simulating software

• Radioss: A linear and nonlinear solver owned by Altair Engineering



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• Range Software: Multiphysics simulation software

• RFEMRFEM

• SAMCEF: CAE package developed by the Belgian company

• SAP2000: American softwareSAP2000: American software

• STRAND7: Developed in Sydney Australia by St d7 Pt Ltd M k t d St 7 iStrand7 Pty. Ltd. Marketed as Straus7 in Europe



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• StressCheck developed by ESRD, Inc USA

• Vflo™: Physics‐based distributed hydrologic modeling software developed by Vieux &modeling software, developed by Vieux & Associates, Inc.

• Zébulon: French software



• Objective and Scope Met– Introduce loads, load factors, and load , ,combinations for nuclear‐related civil & structural design and constructiong

– Present and discuss• Types of loads and their computational principles• Types of loads and their computational principles

• Load factors

• Load combinations• Load combinations

• Focus on seismic loads

• Computer aided analysis and design (brief)• Computer aided analysis and design (brief)


Scope: Primary Documents CoveredScope: Primary Documents Covered


• Seismic Analysis of Safety‐Related Nuclear Structures and Commentary [ASCEStructures and Commentary [ASCE Standard 4‐98]

• Design Loads on Structures During Construction [ASCE Standard 37‐02]Construction [ASCE Standard 37 02]


Completed Items of Overall OutlineCompleted Items of Overall Outline

1000. Introduction

2000. Federal Regulations, Guides, and Reports

3000. Site Investigation


5000. Concrete Structures and Construction

6000. Steel Structures and Construction

7000. General Construction Methods

8000. Exams and Course Evaluation

9000. References and Sources


0401 - E120 - Civil Codes and Inspection - 04 - Loads ...Load Types (ASCE 7‐05) • D = dead load...

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Transcript of 0401 - E120 - Civil Codes and Inspection - 04 - Loads ...Load Types (ASCE 7‐05) • D = dead load...